Abstract - Twenty-eight multiparous dairy cows were divided into 2 groups: one group (S) was fed a ray-grass silage diet and the other one (H) a hay-based diet. The milk produced by these cows was used to make Saint-Nectaire-type cheese on one day and Cantal cheese on the following day, using identical, controlled cheesemaking techniques for each model. The S cheeses, regardless of the model, had higher fat (P < 0.01) and fat in dry matter (P < 0.05) contents but lower total nitrogen content (P < 0.001) and exhibited a more yellow tone. The differences in sensory characteristics were more pronounced in Cantal cheeses: H cheeses had more "butter" and "grass" odours, "citrus fruits" - "hay" -"hazelnut" aromas and more persistent flavour than S cheeses, which showed more "alcohol" odour, "chemical" aroma and had a less "melting", "mellow" texture. The dietary effect was greater with Cantal cheese because of a diet / cheese model interaction.